Predict, Then Test Float

Your child guesses whether each object will sink or float, then drops it in a basin of water to check. The guess-before-you-test step is the heart of it, an easy first taste of making and checking a prediction.

How to do it

1. Fill a basin or large bowl with a few centimetres of water and set it on a towel where your child can reach it. Stay within arm's reach the whole time.
2. Gather a handful of safe objects that differ (a cork, a spoon, a stone, a plastic lid, a coin-sised object no smaller than 3cm for younger children).
3. Hold up one object and ask your child to guess by saying "sink or float?" before anything touches the water.
4. Let them drop it in and watch. Name what happened together without judging the guess.
5. Repeat with each object. At the end, look at which things floated and which sank.

What you need

• Basin
• Water
• Towel
• Small objects

Make it yours

Younger, 3-4 years: Use only three or four large objects and keep the water very shallow. Older, 5-6 years: Sort objects into a "sink" pile and a "float" pile, or ask them why they think something floats. Siblings: Give each child their own object to guess on each round to keep turns fair.